1. Field of the Invention
The present invention relates to a tester for testing integrated circuit packages.
2. Description of Related Art
Integrated circuits are typically assembled into individual packages which have a plurality of external contacts. The assembled integrated circuit packages are tested before being shipped from a manufacturing facility to insure that the product meets certain design specifications. Some producers of integrated circuit packages test 100% of their products. The testing of packages therefore becomes a step in the manufacturing process of the integrated circuit. To reduce production cost it is desirable to minimize the amount of time required to test the integrated circuit packages.
FIGS. 1 and 2 show an integrated circuit tester 1 of the prior art. The tester 1 includes a test board 2 which has a test socket 3. The tester 1 may also have an automated assembly (not shown) which can couple an integrated circuit package 4 to the test socket 3. The tester 1 is typically constructed so that an integrated circuit package 4 can be automatically plugged into the socket 3, tested and replaced by another package.
The test board 2 is coupled to a test arm 5 that extends from a test console 6. The console 6 contains electrical circuitry that performs tests on the integrated circuit package 4. An operator is typically located at the console 6 to monitor the electrical testing of packages 4. The test arm 5 has a movement mechanism panel 7 that can be manipulated by the operator to move the arm 5 relative to the test board 2.
As shown in FIG. 3 the test arm 5 typically has a plurality of pins 8 that are pressed into a plurality of corresponding test pads 9 located on the backside of the test board 2 when the arm 5 is coupled to the board 2. The test pads 9 are electrically coupled to the test socket 3 by conductive routing of the test board 2. The pins 8 are coupled to the console 6 by wire harnesses and other circuit boards (not shown) in the arm 5. It has been found that the test board 2 must be periodically replaced to repair sockets 3 that become defective during testing, or to insert a newly designed board 2.
Test boards 2 are replaced by initially moving the test arm 5 and pins 8 away from the pads 9. The board 2 is then replaced and the arm 5 is moved back to couple the pins 8 to the pads 9. Because of tolerances and other factors, the pads 9 of the new test board 2 may not be in the same position relative to the pins 8 as the pads of the old board. The operator must therefore manipulate the test arm 5 through the panel 7 so that the pins 8 are accurately aligned with the pads 9. A misalignment between the pins 8 and pads 9 may produce faulty test results.
It can be difficult to align the pins 8 to the pads 9. Referring to FIG. 1 the movement mechanism 7 is located at the opposite end of the arm 5 from the test board 2. The operator must therefore move the arm 5 and then walk over to the test board 2 to see if the pins 8 and pads 9 are aligned. This process is typically repeated a number of times. Additionally, it is more difficult to determine whether the pins 8 are aligned with the pads 9 when the test arm 5 is separated from the test board 2 by only a very small space. The time required to aligned the pins 8 and pads 9 increases the overall cost of testing and producing the parts. It would therefore be desirable to provide an integrated circuit tester which minimizes the amount of time required to install a test board.